All patients will be followed in the clinic every 2 months for the first year of the study (weeks 1, 9, 17, 25, 33, 41 and 49) and every 4 months during years 2-6 for a brief history and physical exam, urine and blood tests, return of diary cards (record of drug side effects) and medication review. During the visits from the second year on, patients will also be asked about their ability to do certain ordinary tasks, such as taking care of themselves; ...